About Chameleons:

Chameleons are a majestic animal that seem to instantly blend into their environment, but why and how are they able to do this? Although little research has gone into studying the color changing behaviors of chameleons, researchers have discovered a multitude interesting things about the mechanisms, evolution and function of this unique ability.

Chameleons are a type of lizard found throughout the forest and desserts of Africa, Asia and southern Europe. There are approximately 160 known species which range is size, habitat and coloration. Chameleon's sight is their most important sense, which goes hand and hand with their ability to change colors. The extent of coloration differs from species, as well as the meaning of certain shades. Chameleons utilize their ability to change color in everything from ritual combat to communication to reproduction to defense.

Four Questions

The “father of animal behavior”, Nikolaas Tinbergen, developed an approach to learning and understanding a behavior of an animal. This approach asks four questions:
1. What is the phylogenetic history of this behavior?
2. What is the ontogeny behind this behavior?
3. What is the mechanism of this behavior?
4. What adaptive value does this behavior provide?

Terms Defined

The phylogeny of a behavior in a specific species refers to the evolution of the behavior. The phylogeny describes the origins of a behavior, as well as the selective pressure or circumstances that lead to its current form.

The ontogeny of a behaviors explains how the behavior developed over a lifespan and the degree to which it can be altered through learning. Ontogeny explains if or how certain traits of a behavior develop over an individual’s lifespan.

The mechanisms behind a trait attempt to explain biological construction of a behavior, such as physical morphology, molecular processes, and other biological factors. The mechanism applies the behaviors as it functions in the present.

Adaptive Value:
The adaptive value of a behavior explains the function or survival value of said behavior. It answers the questions: what is the current function of the behavior and how have circumstances lead to the reproductive success and sexual selection of an individuals with said behavior?

This webpage will apply these four questions to explain the color change of chameleons.

Blue Chameleon